The trainer thinks a return to a faster surface will see the 10-year-old in a different light after his defeat by Golden Silver in the Tied Cottage Chase.

"I can't wait to see him back on some nice ground - he loves it. He's a different horse on better ground, absolutely," said the trainer.

Even though Murphy has only been training just over 10 years, he is no stranger to Cheltenham success, having won a Supreme Novices' and a Champion Hurdle with the indomitable Brave Inca.

He went on: "I don't know if there's any more pressure going into the race this year as the champion. It's nice pressure. It was the same with Brave Inca, it's nice to be in this position."

Big Zeb is a general 3-1 chance to win back-to-back renewals behind 9-4 favourite Master Minded, who is going for a third win in the race.

Master Minded was only fourth 12 months ago after winning the two previous runnings of the Queen Mother, and his owner Clive Smith has the utmost respect for the Irish raider.

He told At The Races: "Big Zeb is a very talented horse and if the going gets better it will suit Big Zeb more. We'll be doing very well to see him off and beat him, but I hope we will."

Somersby, meanwhile, got to within a short head of Master Minded in the Victor Chandler Chase over two miles and a furlong at Ascot in January.

Smith went on: "Somersby is a very talented horse and he is a serious contender - though two miles might be a touch on the short side. There's no doubt he's got plenty going for him. We did well to beat him and it was very sticky ground that day. It will be better ground this time."